Abstract: A spring-actuated, hydraulically releasable brake has a brake disc extending between first and second brake pads, a spring assembly urging the first pad towards the brake disc, a hydraulic piston and cylinder assembly for causing a brake releasing displacement of the first pad from the brake disc against the action of the spring assembly and a brake wear adjustment mechanism including an adjustable connection between the first brake pad and the piston and cylinder assembly, a force transmitting motion amplifier responsive to the releasing displacement, a rotatably adjustable connection provided between the piston and the first brake pad and operatively controlled by the force transmitting motion amplifier and a lost motion connection and a one-way clutch between the motion amplifier and the adjustable connection.